As electronic technology and three-dimensional (3D) display technology rapidly develop, a variety of electronic devices that support 3D video reproduction are used in daily life. Accordingly, users can view a 3D video without needing to go to movie theatres. In addition, a stereoscopic depth effect of such 3D video provides users with an enhanced visual experience. At present, research into 3D display technology has become more widespread in the display field.
The principle of 3D display technology is to achieve binocular parallax by providing two slightly different images to left and right eyes, respectively, thereby producing a 3D stereoscopic effect in the brain. For example, the position of a first object 10 in a left eye picture may be different from that of a first object 20 within a right eye picture. Throughout this specification, a left eye picture may refer to a picture provided to the left eye, and a right eye picture may refer to a picture provided to the right eye.
The parallax may refer to a difference between the positions of the same object in left and right eye pictures. In other words, the parallax may refer to a difference between a position of an object on the left retina and a position of the same object on the right retina. For example, when an image of an object is made incident at a distance of 4 mm from the fovea of the left eye and an image of the same object is made incident at a distance of 3 mm from the fovea of the right eye, the parallax of the object may be 1 mm. The parallax may also refer to a difference between a position of an object on the left eye picture and a position of the same object on the right eye picture.
In a stereoscopic display system based on a display screen, the larger the parallax is, the more distinct the out-of-screen and in-screen effect of the object. The out-of-screen effect may refer to a stereoscopic effect in which an object appears to protrude out from a screen, and the in-screen effect may refer to a stereoscopic effect in which an object appears to enter into a screen.
In detail, according to the difference between the positions of the same object on the screen in left and right eye pictures, the parallax may be divided into a negative parallax, a positive parallax, and a zero parallax.